docs: networking: convert framerelay.txt to ReST

- add SPDX header;
- add a document title;
- adjust identation, whitespaces and blank lines;
- add to networking/index.rst.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/framerelay.txt → Documentation/networking/framerelay.rst

-Frame Relay (FR) support for linux is built into a two tiered system of device 
+.. SPDX-License-Identifier: GPL-2.0
+
+================
+Frame Relay (FR)
+================
+
+Frame Relay (FR) support for linux is built into a two tiered system of device
 drivers.  The upper layer implements RFC1490 FR specification, and uses the
 Data Link Connection Identifier (DLCI) as its hardware address.  Usually these
 are assigned by your network supplier, they give you the number/numbers of
@@ -7,18 +13,18 @@ the Virtual Connections (VC) assigned to you.
 Each DLCI is a point-to-point link between your machine and a remote one.
 As such, a separate device is needed to accommodate the routing.  Within the
 net-tools archives is 'dlcicfg'.  This program will communicate with the
-base "DLCI" device, and create new net devices named 'dlci00', 'dlci01'... 
+base "DLCI" device, and create new net devices named 'dlci00', 'dlci01'...
 The configuration script will ask you how many DLCIs you need, as well as
 how many DLCIs you want to assign to each Frame Relay Access Device (FRAD).
 
 The DLCI uses a number of function calls to communicate with the FRAD, all
-of which are stored in the FRAD's private data area.  assoc/deassoc, 
+of which are stored in the FRAD's private data area.  assoc/deassoc,
 activate/deactivate and dlci_config.  The DLCI supplies a receive function
 to the FRAD to accept incoming packets.
 
 With this initial offering, only 1 FRAD driver is available.  With many thanks
-to Sangoma Technologies, David Mandelstam & Gene Kozin, the S502A, S502E & 
-S508 are supported.  This driver is currently set up for only FR, but as 
+to Sangoma Technologies, David Mandelstam & Gene Kozin, the S502A, S502E &
+S508 are supported.  This driver is currently set up for only FR, but as
 Sangoma makes more firmware modules available, it can be updated to provide
 them as well.
 
@@ -32,8 +38,7 @@ an initial configuration.
 Additional FRAD device drivers can be added as hardware is available.
 
 At this time, the dlcicfg and fradcfg programs have not been incorporated into
-the net-tools distribution.  They can be found at ftp.invlogic.com, in 
+the net-tools distribution.  They can be found at ftp.invlogic.com, in
 /pub/linux.  Note that with OS/2 FTPD, you end up in /pub by default, so just
-use 'cd linux'.  v0.10 is for use on pre-2.0.3 and earlier, v0.15 is for 
+use 'cd linux'.  v0.10 is for use on pre-2.0.3 and earlier, v0.15 is for
 pre-2.0.4 and later.
-

Documentation/networking/index.rst

@@ -58,6 +58,7 @@ Contents:
    fib_trie
    filter
    fore200e
+   framerelay
 
 .. only::  subproject and html
 

drivers/net/wan/Kconfig

@@ -336,7 +336,7 @@ config DLCI
 
 	  To use frame relay, you need supporting hardware (called FRAD) and
 	  certain programs from the net-tools package as explained in
-	  <file:Documentation/networking/framerelay.txt>.
+	  <file:Documentation/networking/framerelay.rst>.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called dlci.
@@ -361,7 +361,7 @@ config SDLA
 
 	  These are multi-protocol cards, but only Frame Relay is supported
 	  by the driver at this time. Please read
-	  <file:Documentation/networking/framerelay.txt>.
+	  <file:Documentation/networking/framerelay.rst>.
 
 	  To compile this driver as a module, choose M here: the
 	  module will be called sdla.